ARM: dts: sun8i: v3s: Add simple-framebuffer

Add support for "allwinner,simple-framebuffer"
with "mixer0-lcd0" pipeline from boot loader (u-boot).
It depends on boot loader implementation of DE2/TCON0
setup with LCD.

Signed-off-by: Martin Cerveny <m.cerveny@computer.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20200916175941.8448-1-m.cerveny@computer.org